There are numerous radiator cap removal tools in the prior art. Such tools are deficient because they are not suitable for use with all styles of radiator caps. In addition, use of such tools often places the user's hand so close to the radiator cap that hot fluid is likely to spray the hand when removing the radiator cap from a hot radiator. Many such tools cannot be used on radiator caps that are not mounted on the top of the radiator. Many such tools are specialty tools that have a single purpose. If they are not kept in the car at all times, they may not be available when the radiator overheats.
Often such tools enable the user to loosen the radiator cap, but do not allow the same tool to be used in actually removing the radiator cap from the radiator filler neck. A separate tool, such as a pair of pliers or a rag, which are often unavailable, is needed for actually removing the hot radiator cap.
Furthermore, all such tools are often misplaced simply because they are used so infrequently that the owner cannot remember to keep them with the car, or easily recall where he left them. Finally, many such tools are awkwardly shaped and accordingly, unwieldy in use.
Furthermore, most modern automobile radiators are equipped with a coolant recovery system that collects and condenses vapors escaping from the radiator during operation of the engine. The condensed fluids are returned to the radiator and engine cooling system by ambient air pressure that exceeds the fluid pressure inside the cooling system when the engine cools. When such a coolant recovery system is employed, the radiator cap typically is designed to be loosened by turning about one-quarter turn counterclockwise, where t engages a pressure release stop-tooth on the outer flange of the radiator filler neck. When the radiator cap is in this position, vapor pressure will be released from the radiator and cooling system, but the cap cannot be removed from the radiator filler neck, thereby reducing the chance of injury from splashing hot fluid. After the cooling system pressure reaches equilibrium with the ambient air pressure, the radiator cap can be safely removed by depressing it firmly and rotating it approximately another one-half turn counterclockwise, allowing the radiator cap to be lifted free of the filler neck. Most tools for removing radiator caps, including the human hand, require the user to press down hard on the radiator cap to develop a sufficient grip to overcome the friction between the radiator cap gasket and the lip of the filler neck and to rotate the cap.
When the radiator cap is thus depressed, it is very easy, and all too common, to rotate the radiator cap past the pressure release stop-tooth. If this happens and the radiator is hot, the cap is likely to be explosively thrown from the radiator as superheated fluids gush out the radiator filler neck, and injury to the person is very likely. Such injuries can be very serious and may include, for example, the loss of sight. In addition, exposure to antifreeze can seriously damage the car's paint.
Therefore, a need exists for a tool for removing radiator caps that can be used without modification for all styles of radiator caps; that will keep the user's hand sufficiently removed from the radiator cap to prevent hot fluid from spraying the user's hand; that will conveniently remove a radiator cap that is not mounted on the top of the radiator; that is easy to use; that will not become lost; that is always available when needed; that can easily be used for actually removing the radiator cap from the radiator neck, as well as for loosening it; and that is simple and inexpensive to design and manufacture.